21937968 has 60 divisors (see below), whose sum is σ = 66124240. Its totient is φ = 6749568.

The previous prime is 21937943. The next prime is 21937969. The reversal of 21937968 is 86973912.

21937968 is a `hidden beast` number, since 219 + 379 + 68 = 666.

It is not an unprimeable number, because it can be changed into a prime (21937969) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3988 + ... + 7731.

Almost surely, 2^21937968 is an apocalyptic number.

It is an amenable number.

21937968 is an abundant number, since it is smaller than the sum of its proper divisors (44186272).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21937968 is a wasteful number, since it uses less digits than its factorization.

21937968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11746 (or 11737 counting only the distinct ones).

The product of its digits is 163296, while the sum is 45.

The square root of 21937968 is about 4683.7984585163. The cubic root of 21937968 is about 279.9403274198.

The spelling of 21937968 in words is "twenty-one million, nine hundred thirty-seven thousand, nine hundred sixty-eight".